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Everything posted by flintgreasewood

Late December last year I began digging a 6' x 6' prospect shaft about 100' downstream from the original Cobb prospect shaft. Armed with a 30 lb electric jack hammer, a couple of shovels and my nifty 1/2 size home made "Fairbanks self dumping bucket" system I worked my way down through frozen muck and eventually a 10' gravel layer to bed rock at 62'. On my way down I encountered layers of tangled branches and trees up to 6" in diameter. After 40+ feet I hit fine sand and scattered patches of gravel, fossil bone fragments, then complete bones. I was anticipating these finds but the excitement of actually finding them was intense. The first chunk of mammoth tusk nearly put me over the top. Progressing downward, the bones became less frequent and the pay gravel more dense. I had been told that a jack hammer would be ineffective in frozen gravel. Good I don't listen to everything I hear; it busted up almost as easy as the muck. The gravel graded into fractured and decomposed bed rock and I knew I had finally reached my goal...10 months after starting the project. Before freeze up I was able to wash 5 yards of pay and the result was encouraging. I'll have to wait till late spring to resume processing what I brought up before and what I can hoist this winter.
Now it's late November and all is solidly frozen above as well as below ground. Since bottoming out in the shaft I've been devoting most of my time to upgrades above the shaft in preparation for winter work. Also I had to take a part time job in town to help pay for the added expense of moving to a small cabin also in Fairbanks. What little time I've been able to devote to underground efforts have been to expand my working space. On the way down I managed to increase the dimensions of the shaft from 6' x 6' to over 7' square. The plan is to continue out to 10' square before I begin pushing the drifts across the valley.
Jack hammering straight down is relatively easy compared to working horizontally and even vertically. Sufficient pressure is difficult to exert out of position so I began working on ideas to free the gravel other than by the traditional steaming or blasting to reduce the great amount of physical labor involved with jack hammering. Suffice it to say, I'm making good progress in those efforts. I'll report on this process in months to come.

It's almost summer, though it still doesn't feel like it. I prepared well for spring run off by removing snow from all around the shaft area, tons and tons of snow and all by hand. It was good to get my body ready for mucking pay. I've had reasonable success thawing gravel with my heat rods and I'm getting more efficient with the drilling apparatus. But just when things were clicking along, my generator died on me mid way in a thaw. I tried repairing it but had no immediate success so I decided to have another try at getting my 8K Lister running. I've had the Lister for over a year and never been able to get it started. So I removed the injectors and tubes, checked for good fuel pressure, tightened all connections, adjusted valve lash and made as sure as I could all the air was removed from the system and gave it a crank. It fired up. Yessss. And I had good voltage off the generator. Now the job was to get it down to the shaft. I strung a log chain between two trees on either side of the generator, raised it off the ground with a come along and dropped it into my Otter sled which I then pulled down the hill to the shaft with the wheeler. Since there were no trees there to work with I rigged up a tripod tall enough to do the same hoist procedure out of the sled. The final 20 feet were accomplished with a chain saw winch. I fabbed an outlet junction box from an old generator, mounted it in the hoist shack and ran a power cord from the Lister to the box. All was in place for power down in the shaft. Couldn't get it started again. I had replaced all the filters and found the main fuel filter had a second gasket that was not supposed to be there, so I took that out. Air must have been getting through at that point. Also I discovered the former owner had incorrectly plumbed the water separator. I re bled the system and hooked up a brand new battery. It started and ran just like it came from the factory. Praise God. I now had power. I could get down to the bottom of the shaft and see what headaches were awaiting me from the rain and melting shaft ice that had accumulated over the two weeks I was without power.. It was a mess, but I got my deep well pump running and removed what water had not yet frozen (a considerable amount). Loose ice was shoveled into the hoisting bucket and the remainder I busted up with the jack hammer and hoisted it out. A number of tools were coated with ice and had to be knocked clean and or thawed out up top. Now I can get back to the incomplete thaw I began three or four weeks ago; the rods are still in place. It will take an additional 20 hours to complete, but at least I'm back in business.

I worked for an operation that used a very large rubber lined pump to suck the gravel coming off a 250 yd per hour trommel The 1/2"- slurry was pushed about 75' through an 8" pipe then up 10' on to a monster jig. It took a 100hp motor to run the pump but it sure did the job. I'm sure you could go smaller but you're still going to have to have some pretty heavy horse power.

Not an awful lot to report. I'm about 9' in my drift which is about 5' wide and 5' 6" high at the top of an arch. My gravel is very atypical with large lenses of pure muck in between a jumble of chunky, fine and ground up shist bedrock, large cobbles, angular and rounded quartz and a smattering of intrusives. There's no bedding or layering except for the muck and I even have bones almost to bed rock, one of those being a young mammoth jaw complete with two teeth found 2' off bed rock. It's quite a conundrum. And the gold is not primarily just off bed rock but spotty and scattered throughout the entire column. Got any ideas? Heavy flood event?? I'm also continually making changes to my heat rods for the gravel thawing. My latest iteration should be ready to test out in about 2 weeks. From calculations and prior experience I'm expecting some really effective thawing. I'm also improving my drilling system making it faster and less labor intensive. My bucket hoist has been working nearly flawlessly. I'm ready for the cold to leave though I'm not looking forward to fighting with runoff again this year. Got some ideas how to mitigate it. More soon. Thannks all for your continued interest.

Hey guys, sorry for taking so long to respond. I'm back down in the hole where it's much warmer than top side. Finally got all systems working well enough to initiate another round of drilling and thawing in my main drift. Unfortunately, my heat rods weren't working like I had hoped they would and produced an uneven thaw. Consequently I had a fairly thick wall of frozen gravel on the face and well thawed gravel behind which necessitated a good bit of jack hammering to clean it all out. So I brought all the rods home and reworked them so they'll heat more evenly and also run a good bit hotter. I'll be testing them over the next two days.
My young help disappeared when the snow and cold hit and put an end to above ground work. I may get them back soon. The began putting down a new shaft about 150' from my shaft which I'll eventually connect to via my drift. We're thinking the main pay streak is much closer to being below the new shaft.
I'm developing a system for operating my hammer drill that allows me to simply set up the various support members, position the drill and then just turn a crank handle to either pull the drill bit into the wall or retract it. I've already drilled about 20 holes using the system and now I'm just simplifying it. Hopefully soon I can include some videos and photos of the operation. Well, that's about it for now. Stay tuned.

JR Thanks for your continued interest. I'm back in town for the fall and winter[back on line] so I can update easier. It was a slow season for pushing the drifts in my shaft. I spent much of the summer upgrading infrastructure, as it were...new gin pole, new shaft deck, new dead man, etc. Also had water issues that have been so aggravating I just didn't want to be down in all the wet. I did get some thawing done and am very pleased with the performance of my home made thawing rods. I'll start back in the drift as soon as things freeze up good. We're also prospecting an old mine's dump piles [not tailings] and will try to keep that going even after freeze up. Got a couple of young guys helping me out now. Sure nice to have the extra muscle, enthusiasm and company.

I'm looking for someone to mine roughly 2 miles of virgin permafrost placer stream valley close in to Fairbanks. The overburden ranges from about 45' to 80' so it would require an operation not afraid of going deep. Pay gravels are 8' to 10' and contain gold for nearly the entire horizon. Though the ground has not been drilled, there are several prospect shafts that indicate values of a minimum of 1 oz per 30 yds.. The history of the creek below my claims is rich and much research has been done re. geology and production. Ground is a mile from major highway and town is less than 1/2 hour distant. A prospective operation will need to drill the ground and have large dozers w/rippers, rock trucks or dragline and excavators. There is a large spring that can supply sufficient water for processing. If interested contact Kurt

Hey, Leonard...good to hear from you again. Been past that mill many times on my mountain bike. Just love James Canyon and all the mining in that area. It would be great to see renewed activity up there again, but bucking the greens of Boulder County is pretty daunting. Come on back up here to Fairbanks and see my operation this summer.

Hi, Steve, Harry, Chris and other interested miners,
My first reaction in response to Steve's last post is: where does the money come from to drill, rip with a dozer, excavate, haul material, build access road, site grade, etc? It's going to take someone or some operation that has a very good knowledge of the immediate area and its potential and, therefore, is willing to take the risk to get some firm numbers. Next, frozen muck drills fast, but 80' holes are still not cheap. I'll try to get some costs. Working with a dragline is probably the most cost effective way to remove overburden and currently there is a good possibility of a 2 1/2 yarder available. If operations were to begin at the furthest downstream point that would be just past where the two feeder creeks joined, thereby combining two pay steaks. That would surely be the richest ground. Drilling might best begin at the division of the creeks. I'd like to think that by summer's end I'll have good knowledge of the pay on the upper end of Vault [more than 1/2 mile above the junction] from drifting out of the shaft I've put down. So, how serious are you about my ground, Steve? What could you bring to a venture? How similar is a "syndicate" to a partnership?

You are right, Chris, about the thawing muck. It certainly presents problems but there are mining operations in the Fairbanks area that routinely tackle frozen overburden as deep or deeper than my ground. Frozen muck rips easily, so you do all your overburden removal beginning in the fall after freeze up. Take a break in December and January and get back with it till June when it really warms up. There's plenty of room in the valley to stack overburden. So by June you have a patch of pay gravel 150 to 200' wide by, say 200 feet deep by 10' thick, That's about 15,000 cu yds. Based on historical reports of gold produced downstream on Vault Creek I'm convinced the pay could easily run over $100. per yd. That would come out to around , $1,500,000. Of course drilling first is essential, and what I find in my drift tunneling will enable us to put some numbers where up to now there is only speculation.

Hey guys
I have approximately 10 feet of gravel on top of bed rock. I'm only beginning to run my drifts across valley so I'm not able to say what the angle of bed rock is yet. Now I'm recovering from back surgery [relatively minor] but it's going to keep me from any vigorous mine work for several weeks. Ahhh, patience!

Hi Chris
It's almost February and I'll soon be starting my cross valley drifts. In anticipation of increased material removal I am beefing up and enlarging my hoisting system. Should be an exciting season. Good luck to you

JR, Good to hear back from you. The seepage into the shaft ended shortly after freeze up. All is nice and dry down below. I'll be digging a substantial trench up stream this spring to hopefully divert any flow into the shaft next summer. Let's hope it works.

Thanks, Doug I hope my efforts serve as an encouragement to other current and future drift miners. I'm hoping to develop simple systems that can be utilized by even just one person to successfully mine underground.

For those who have been following my odyssey some real progress has been made on my new shaft in the past two months. It's been one hard slog to jack hammer my way down to 55' but persistence is paying off. I'm now in mixed gravel and muck and will be into some gold in a few more feet. The gravel is proving to be more difficult to jack hammer than I had hoped though it varies around the shaft. Some will be almost dry and breaks up easily and other places it will be as hard as concrete. What keeps things interesting though is the fossil remains I'm uncovering. Just today I pulled out a mammoth metatarsal [toe bone]. Last week I chipped out a 5 lb. chunk of mammoth tusk. It's likely I'll be finding full tusks as I drive the drifts. Hoisting is going quite well though I have to watch the weight in the bucket as the gravel is substantially more heavy than the muck and my motor overheats if I overload or send up a bucket without letting the motor cool down a bit. I'm getting ready to run some heavier electrical wire so that should help with voltage drop. We'll be building a new boiler house shortly and setting up the steam system though we may be experimenting with some different methods of thawing.
More to come soon.

A few months ago I was frustrated with my inability to get anywhere with the old Cobb prospect shaft. Between then and the end of 2015 I fiddle farted around with reconfiguring my steam system and making my work shacks semi habitable in the extreme cold that was to come. When the temperatures here in the interior of Alaska insisted on staying well above 0 it came into my head to put down a new shaft. Earlier in the year I had carefully walked the area directly downstream from the old shaft looking for possible sites. Though the ground was now covered with 2 feet of snow I easily relocated the chosen spot. With my trusty aluminum scoop shovel I removed the snow from a large area and went at the frozen moss and brush with a pick adz. Darkness crept in slowly even though it was only 4:30 so I ran a 100' extension cord from the camp, set up my flood lights and worked on into the night. Integral to a new shaft would be a new gin pole and I figured I'd have to cut down a large spruce, drag it a couple hundred yards, jackhammer out a pit in the frozen ground and rig up a hoisting system to raise it up in place. The prospect of all that work caused me to rethink the positioning of the gin pole and it hit me that I merely needed to run my highline to the tallest, sturdiest spruce 90 degrees from where I had originally thought to place it. I wouldn't need a pole that would have to be in service for many years...just a year or two. And if I needed something more substantial later on I could take care of that in the spring. I found the right tree, brought in my 18' ladder and proceeded to position eye bolts and guy wires for support.The high line would need to be anchored behind the shaft and to do that I had to dig a pit in which to set a "dead man". However. the angle of the high line over the shaft area would be too low to allow a bucket to exit and clear the shaft wall. I had to rig an elevated support, a "quad pod" of spruce poles between the anchor point and the shaft that effectively raised the high line 5' above the shaft. I'll have to hang the bucket to determine if the high line is elevated enough. Once I had the high line in place I could begin filling the dead man pit, but with what? I didn't want to use frozen muck with its high water content. I opted for gravel and the best and closest source for that was the pit we've been slowly excavating for our outhouse. Of course that gravel would be frozen so I loaded up the generator, jack hammer, shovels and weed burner in the sled and zipped on up to the cabin. The jack hammer doesn't work properly when it's cold and that's where the weed burner comes in. I spend a few minutes warming up the jackhammer and my gloves and everything works much nicer. I underestimated the amount of gravel I needed to fill the dead man pit and had to return for another load. To insure a strong dead man I dumped in 10 gallons of water to freeze it into one solid block. Now I'm working on an electric hoist and as soon as I can get it operational I'll be able to begin actually digging out the shaft.

Here's a brief update on my work at Cobb prospect this season. I'm now down to the 40' level in my 6x6 shaft. It hasn't been easy with problems of spring snow melt, a snapped gin pole, endless modifications of the hoisting system. trails turning to mud bogs. dying jack hammers and just plain gettin' older and tireder. The gin pole situation was nearly fatal as it allowed the full bucket to be free to return to the shaft and fall 25' to land right at my feet...a real heart stopper. God is good and saved me from harm. I now have a full size 2" x 10" x 10' plank that I used as a shield every time I hoist or lower a bucket. Don't wish to put God to the test again so soon. Then I had to cut and drag into position a new and larger pole to replace the broken one. Raising the 34' spruce with tripods, come along, a small electric winch and lots of guy wires was no easy trick, but I managed. The trail turned bog forced me to find a new high and dry route to the prospect but that entailed crossing Vault Creek and two little pups. To do that I had to build three bridges, two of them 30' long and one 10'. That's a lot of 4" x 4' poles. While pitching some of those poles I threw out my back and an MRI determined I ruptured a disc in my lower back. So I've been limping around for 6 weeks with a numb foot [pinched nerve] and am awaiting laser surgery in late Aug. Fortunately, I am not in pain and can still work in the shaft as normal. I now have all systems working to near perfection with a new jack hammer and even a small hoist dedicated to hauling me up and down the shaft instead of having to use the ladder...a real energy saver. Just the other day I noticed my bucket refused to lower into the shaft. I determined the dead man that was anchoring the main high line was giving way so that the line was too slack. Fortunately, I had several 3 1/2 foot lengths of 1" rebar that I had ground points on. I drove three of them in line 3' apart and connected them base[ permafrost frozen just below the moss] to top and attached the high line to the first one. It has so far proven to be a fine dead man setup. I made sure the posts are well insulated and protected from possible rain.
It's been a lot of hard work and sometimes discouraging with the slow pace I am going but I'm learning patience. I have only 16 to 18 feet to go to hit gravel and then things really get exciting. I'll let you all know when I get there. Till then, have a great rest of the summer mining season.